How to make seaweed fertilizer?


If you live near the coast, seaweed can be a fantastic resource to forage for fertilizing your garden. There’s lots of easy ways to use it to increase the health of your soil, and your veggies and flowers too.

First of all, check the local regulations where you live around collecting beach-cast seaweed. Collection is fine in some places, and not so fine in others – this post has links to the regulations in Australia.

Once you’ve got the all-clear, always remember to practice responsible foraging and harvest lightly from within the tidal zone – there’s lots of animals, birds, insects and other organisms who also consider that beach cast seaweed valuable, so leave enough to go around.

We’ve used everything from shopping bags to a pull-behind trolley to harvest beach-cast seaweed. How you roll is up to you.

Some people consider the older seaweed stinky or dirty, but to me, it’s just organic material that’s decomposing – and it smells a lot better than plenty of other decomposing organics I’ve worked with!

Once you’ve got your seaweed home, there’s several ways you can use it in your garden. Which method you use will depend on your garden, and you. Generally we don’t wash our seaweed unless it’s going into seaweed tea.

Why use Seaweed in your garden

Seaweed contains ALL the elements (wow!) but most only in trace amounts – it does however typically contain useful amounts of: iodine, copper, manganese, potassium, phosphorus, iron and zinc. It’s typically used straight up, as a compost addition, or as a brewed seaweed tea.

In either form, seaweed is used as a great soil conditioner which helps build a healthy soil food web in your garden. It’s liquid form is also used as a foliar spray for ornamental and edible gardens alike.

Seaweed tea is known for starting strong seedlings and producing resilient vegetables (it’s a huge help against marginal frosts) as well as improving veggies transport and shelf life.

And as we all know, super healthy plants means less pest problems, longer fruiting periods and general garden goodness.


You can use seaweed to mulch around and underneath your plants straight up. It will decompose faster if it is underneath another layer of mulch, or go dry and crinkly and decompose slower if it’s the top layer – mulching with seaweed is good for:

  • Instant organic fertilizer solutions! Lay it down, and you’re done. Boom.
  • A great broad-spectrum, slow-release fertilizer for plants
  • As a dried-out spiky top layer it’s helpful for deterring snails, slugs and some household pets too
  • As a faster-decomposing under layer it’s also great for slug control, as the slugs dislike the small amount of salt
  • Weed free mulch! No embedded weed seeds here, unlike many straw mulches
  • Doesn’t blow away in the wind like some mulches can
  • Organic (ish) – if gathered from clean waters and not near ocean outfalls, your seaweed should be a healthy addition to your garden.
  • In sandy soils, the alginates in the seaweed (particularly bladder wracks) can really help as an additional wetting agent

Basic Seaweed fertilizer tea

Home made seaweed tea is a great addition to any garden that’s packed with plant-friendly nutrients – we love it because it can be made seasonally when the seaweed shows up, and then used throughout the year.

You can make straight-up, single ingredient seaweed tea, or combine it as we do with other nutrient and mineral-packed plants, for an all-round liquid fertilizer.

Either way, the process is basically the same. Here’s how we make our Seaweed tea, with comfrey, nettle and borage.

You will need:

  • A bucket or barrel with lid
  • As much seaweed as will fit in your bucket
  • Comfrey, nettle + borage leaves
  • Non-chlorinated water (rainwater is great! go catch some)
  • A stick for stirring
  • A shady spot to stash your bucket for the duration

Fill your bucket with lightly washed seaweed, and add your herbs and other leaves. Fill to top with water, and place somewhere out of the sun (maybe not next to the front door, it will smell at certain stages of brewing), with the lid on lightly, but not tight.

Stir the brew with your stick each day for a week or so if you remember.

Then wait, for about 3 months.

During this time, the tea mix will start off aerobic, which smells fine, then slowly go anaerobic, which is the stinky stage. Fear not, leave it alone, and push on.

After a few months or so (the timing depends a lot on your ambient temperature, this mix will progress faster in Summer than Winter) the anaerobic stage gives way to a second aerobic stage (as more good bacteria have moved in), at which point your seaweed tea will smell good again. And now it’s ready to use!

You’ll probably find that most, if not all, of the seaweed and leaves have broken down entirely, or there may be some sludge at the top, or bottom, of your bucket.

While this sludge is liquid (sludgy?) gold, it’s best put in your compost pile rather than straight on your plants, as it’s concentrated goodness and might be a bit much for them.

You can pour the liquid off into another vessel from the sludge for applying to plants, or leave it in the same vessel – its up to you.

Dilute your concentrated seaweed tea 1:10 with water, and apply to plants and seedlings weekly for very healthy veggies that are packed with extra goodness.

Extra goodness from the added herbs:

Comfrey + Borage: potassium, nitrogen, phosphorous | Nettle: Nitrogen + trace minerals

Variations: You can also aerate your seaweed tea throughout the brewing process with a small aquarium oxygenator, or a snazzy compost tea brewer – this will shorten the brewing time dramatically and cuts out the stinky stage, but obviously requires more energy inputs.

You can also add microbial inoculants to your seaweed tea to increase microbial activity and speed up the process that way, as well as possibly enhancing the result – these can be got at some garden stores or online.

Live somewhere where seaweed harvesting is not possible? You can buy dried kelp from most rural stores where it’s sold as an animal feed supplement, which works fine in the above recipe.

Using Seaweed tea

You can use Seaweed tea at the 1:10 ratio on the soil of your garden, and also as a foliar spray for plant leaves.

The seaweed tea can be helpful anti-fungicide against powdery mildew and some other fungal diseases, and it’s also a helpful pest deterrent.

Diluted seaweed tea is also great for seedlings, as it contains some natural hormones that aid plant growth. We use it frequently as the liquid in our soil blocking + seedling mixes, as well as in seedballs.

If you can’t access or make the home made stuff, there’s also liquid seaweed products like Seasol that are made of kelp from Bass straight and knotted kelp from the north atlantic – another option for happier plants.

A note about home-made compost + seaweed teas: Caution when handling the tea if you’re pregnant is a good idea, especially during the anaerobic stage.

As with any natural brew, use common sense, high-quality ingredients, and if it smells badly wrong at the end when it should smell great, don’t use it.

Do you make seaweed fertilizer at a small or large scale? What do you use? Got any recipe tips for us? We’d love to hear…

Keen for more seaweed info? Check out Foraging, Drying + Eating Seaweed in Australia…

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How to Make and Use Seaweed Fertilizer

I’m sold on using seaweed fertilizer, whether fresh or purchased—and as people try it for themselves, they’re also learning its benefits.

As a commenter on my YouTube Channel writes:

“Dude it worked!!! My plants have grown very well with washed seaweeds! I use or twice every week and it is working awesome! Ive never had such growth before!! wow! Thanks man! God bless you….never listen to those who say negative things on you…You are doing great! God bless you.”

Thank you! God has blessed me and continues to do so. And I count the abundance of free local seaweed as one of those blessings.

Over a year ago, I posted this video on making and using seaweed fertilizer in the garden:

If you live far from the beach or don’t feel like hauling bags of seaweed, you can get good seaweed fertilizer on Amazon. Neptune’s Harvest is a popular one and is really rich since it’s a mix of both seaweed and fish. Fish emulsion is like magic in the garden—and when you mix it with seaweed, you’re really adding the bounty of the ocean to your plants. They go crazy. In fact, my friend Jo the Master Gardener once told me that fish emulsion is the way to grow truly awesome organic strawberries in Florida. It greens them up and makes them fruit without encouraging leaf growth over fruit.

Another option that I used to use on my beds in North/Central Florida was kelp meal. It’s loaded with minerals and a little goes a long way. I don’t know if kelp is totally safe post-Fukushima, but I haven’t heard anything really scary lately.

I added kelp meal to the fertilizer mix I used to grow these amazing cabbages:

I followed the directions for making Complete Organic Fertilizer, which Steve Solomon writes about in Gardening When it Counts. Once I had my mix, I sprinkled it all down the beds, raked it in, put down a weed barrier, punched holes, then planted cabbage seedlings. They did better than any I’ve grown before or since—absolutely beautiful heads.

Seaweed was part of that. Consider it a multivitamin for your garden, loaded with micronutrients. The big three (nitrogen, phosphorous, and potassium) are the main course—and seaweed has those, but not in huge amounts. However, seaweed is really rich in the little things that add to the overall health of your plants.

How to Make and Use Seaweed Fertilizer

So, you have some seaweed and want to try it out? Here are three good options.

Option #1: Seaweed as Mulch

Take the seaweed, rinse it out, then use it as mulch. That works nicely and breaks down over time. Maritime Gardening agrees:

Option #2: Compost It!

Put seaweed directly into the compost pile. Consider it a “green” layer. I don’t bother rinsing it when I do this, figuring the salt on it will work its way through.

Option #3: Make Liquid Seaweed Fertilizer

You’ve seen me do this before with weeds, manure, kitchen scraps, etc.:

You can do it with seaweed, as well. It’s a great additive—or it can be used all by itself.

This is a very good video where a man uses the same method I do, but with comfrey and other northern leaves, along with seaweed:

Hey, that guy looks way more pro than me. I should send him a T-shirt.

Now, go—find yourself some seaweed!

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David The Good is a Grow Network Change Maker, a gardening expert, and the author of five books you can find on Amazon: Compost Everything: The Good Guide to Extreme Composting, Grow or Die: The Good Guide to Survival Gardening, Totally Crazy Easy Florida Gardening, Create Your Own Florida Food Forest, and Push the Zone: The Good Guide to Growing Tropical Plants Beyond the Tropics. Find fresh gardening inspiration at his website and be sure to follow his popular YouTube channel.

I am always in awe of the fact that there is a garden under the sea; that plants can not only survive but thrive in a watery world that is turbulent and ever changing.

Seaweed is magical stuff in the water, and it’s somehow even more so when out of it. It’s incredibly healthful to us, to our animals, to our soils and our plants. It seems anyone who gets to ingest a little seaweed does better for it.

As seaweed breaks down into the soil, it encourages microorganisms whose activities help convert unavailable nutrients into forms that plants can use. It increases chlorophyll production and contains many micronutrients important for soil and plant health, as well as acting as a growth stimulant: it is rich in cytokinins, plant growth hormones that work above and below ground, improving root growth.

I recently went to Inagh Valley Trust, a seaweed research centre in Connemara, Ireland. They’re developing all sorts of interesting seaweed products, including adding seaweed to manufactured bread to increase its shelf life, and creating a seaweed feed for honeybees, to improve hive conditions and combat disease.

I spent a morning geeking out on seaweed spores swirling around in glass jars as they went through propagation, and munching on seaweed health bars. Then I went to the coast and wondered how much beach-strewn seaweed I could cram into my suitcase home – and whether Ryanair would complain about the smell.

It’s very important to collect only seaweed that has washed up; it’s not sustainable for everyone to go around the rocks pulling it off. Winter storms, however, often wash up great mountains of the stuff. There are brown, red and green algae, and all have different nutrient levels, so collect a variety, if you can. In general, seaweeds contain 10 times the mineral levels of land-based plants and are particularly rich in iodine and calcium. You can put them directly on beds; they will be salty, so you can’t plant direct into them, but a winter of rain will wash the excess salt away.

If you don’t have beds that are suitable for such methods, add the seaweed to your compost, or compost it on its own. Once broken down, it’s the magic ingredient for growing thin-skinned new potatoes, as well as for top-dressing pots, where it will act as a mulch while continuing to break down. Rotting seaweed is always hopping with life. Springtails (little jumping insects) seem to love the stuff, but don’t be put off; it’s part of seaweed’s magic that everyone wants a part of it.

If you are nowhere near the shore, you’ll have to buy some. And it’s well worth it: if I had the money for only one type of fertiliser, it would be seaweed. There are numerous brands; I like the Irish one called Seafeed, which does pure seaweed meal, just dried and ground. Whichever you use, your garden will thank you.

The Seaweed Site: information on marine algae

Liquid Seaweed Extracts

Liquid extracts of marine brown algae are marketed for use in agriculture and horticulture (for some early information see Booth 1969; download pdf here). Many of these extracts are prepared from dried Ascophyllum nodosum meal (e.g. “Maxicrop”, manufactured in the United Kingdom and a range of products tailor made for particular crops from Brandon Products), or from dried total drift, often referred to as “blackweed”, but some utilise other species, such as Fucus serratus and Laminaria species (e.g. “SM3”; United Kingdom). One product currently being marketed is prepared from the stipes of Ecklonia maxima from South Africa (Kelpak). Other products prepared from seaweed include Algea, from a Norwegian company, “Seagro”, manufactured in New Zealand; and “Seasol”, an extract manufactured from Bull Kelp (Durvillaea) by a company in Tasmania, although some of these may have ceased trading. These are prepared from either cold- or hot-water extracts of either the dried or wet seaweed, sometimes with the addition of sodium carbonate to aid extraction.

“Maxicrop” is primarily used for gardens and glasshouse crops and is exported to a wide range of countries (Chapman & Chapman, 1980). It has been used on citrus fruits in Guyana, on citrus and grapes in Greece, on orchids in Belgium, on garden crops in Thailand, and on glasshouse crops in Iceland. “Seagro” in New Zealand is largely used on pastures but it is also used on orchard crops.

A wide range of beneficial effects have been reported from the use of liquid seaweed extracts (Blunden 1977), including increased crop yields, resistance of plants to frost, increased uptake of inorganic constituents from the soil, more resistance to stress conditions, and reductions in storage losses of fruit.

Liquid seaweed extracts are used at very high dilution rates which results in only very small quantities of material being applied to a given area. The active substances in the seaweed extracts must therefore be capable of having an effect at a low concentration. Trace elements have been suggested as likely active constituents, but Blunden (1977) and Blunden & Gordon (1986) have concluded that the quantity of substances applied forms an insignificant proportion of the total requirements of the crops. The presence of plant hormones (substances naturally found in small quantities in plant tissues and involved in, amongst other things, the regulation of growth) has been suggested as being responsible for, at least some of the observed effects; it has been demonstrated that commercially-available seaweed extracts have high levels of cytokinin-like activity.

Close correlations between results achieved in field trials with the use of a synthetic cytokinin, kinetin, and seaweed extracts of equivalent cytokinin activities were found both on the yield of potatoes and in the crude protein of grasses. Similar results were obtained with the reduction in the rate of “degreening” of limes after post-harvest immersion of the fruit in seaweed extracts and kinetin solutions of equivalent cytokinin activity. Further circumstantial evidence supporting the possible involvement of cytokinins in seaweed extracts was the recent detection of cytokinin-like activity in a commercial seaweed concentrate prepared from Ecklonia maxima (Laminariales).

Studies of seaweed extracts have shown that although in some bioassay systems, for example the radish leaf expansion bioassay, high levels of cytokinin activity are recorded, in others, for example the Amaranthus seedling assay, low levels are found. These discrepancies are thought (Blunden & Gordon 1986) to be due to the extracts containing, in addition to true cytokinins, other compounds which behave like them in certain respects. Blunden & Gordon were further of the opinion that these substances may represent betaines – quaternary ammonium compounds which are derivatives of either amino or imino acids containing a fully methylated pentavalent nitrogen moiety. Glycine betaine, one of the structurally simple betaines, was first extracted from sugar beet and was found to have chlorophyll-retention properties. In growth tests it was found to have an activity similar to that of cytokinins in several other growth tests and so it was considered that some of the cytokinin-like activity in sugar beet extracts was due to glycine betaine. It has been shown also to be a major osmoticum (controlling water movement in and out of plant cells) in certain higher plant families adapted to either salt or water stress and it has been suggested that other betaines and tertiary sulphonium compounds have a similar function in other species. Also it has been claimed that glycine betaine has a rôle in frost resistance.

Betaines have been recorded for most of the species of marine algae used in the manufacture of seaweed extracts. Ascophyllum nodosum yields c-aminobutyric acid betaine, d-aminovaleric acid betaine and laminine whilst Laminaria species have a range of betaines including glycine betaine. Commercial seaweed extracts have been examined for their betaine content and the compounds detected were those reported for the algal species used in the manufacture of the extracts. Because of the reported effects from the application of commercial seaweed extracts and the known properties of compounds such as glycine betaine, the circumstantial evidence for at least part of the activity of the seaweed extracts being due to compounds of this type is strong (Blunden & Gordon 1986). Moreover, some of the discrepancies in the results obtained for the cytokinin contents when the extracts are bioassayed using different procedures may be explained by the presence of betaines in the extracts.

Manufacturers of liquid seaweed extracts in Ireland

  • Brandon Science
  • BioAtlantis
  • Celtic Moss

Photographs courtesy of Paul Mullins, Brandon Science Ltd, Centrepoint, Tralee, Co. Kerry, Ireland. Phone: +353 66 7181160

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CN102488253B – Preparation method of active seaweed extract
– Google Patents

一种活性海藻提取物的制备方法 A method of preparing an active substance seaweed extract

技术领域 FIELD

本发明涉及海藻提取物领域,尤其涉及一种活性海藻提取物的制备方法。 The present invention relates to the field of seaweed extract was, in particular, relates to a method for preparing active seaweed extract.

背景技术 Background technique

褐藻是海洋植物中的主要成分。 Alginate is the main component of marine plants. 褐藻中的海带、昆布、裙带菜、羊栖菜等均可食用和药用;马尾藻属植物可作饲料或肥料。 Seaweed, kelp, wakame, hijiki etc. Edible and Medicinal brown algae in; Sargassum plants can be used as feed or fertilizer. 此外,还可从海带等褐藻中提取褐藻胶、甘露醇、碘、氯化钾、褐藻淀粉等食品或医药用原料。 In addition, also extracted from seaweed and the like in alginate alginate, mannitol, iodine, potassium chloride, starch, alginate and other raw material for food or medicine.

褐藻中含有丰富的营养物质及活性物质,还含有维生素A、B、C及微量元素硒、钴、铬等营养成分,同时褐藻还含有大量的非含氮有机化合物以及未知的促生长素。 brown algae rich in nutrients and active substances, also contain vitamins A, B, C, and selenium, cobalt, chromium and other nutrients, but also contains a lot of non-alginate containing organic compound, and unknown growth promotion Su. 褐藻中所含有的矿物质和微量元素多以有机态的形式存在,不易被氧化,便于动物吸收,其效应和动物吸收能力优于无机矿物质;其含有的脂肪酸大部分为不饱和脂肪酸,主要为亚麻酸、次亚麻酸和二十碳五烯酸(EPA)等必需脂肪酸。 Minerals and trace elements contained in the multi-alginate present in the form of organic state, susceptible to oxidation, facilitate the absorption of animal, its effect and the absorption capacity over inorganic mineral animal; fatty acid which contains mostly unsaturated fatty acids, mainly linolenic acid, eicosapentaenoic acid and linolenic times (EPA) and other essential fatty acids. 其中海带是地球上含碘最丰富的食物之一,海藻粉可直接作为碘源添加到食品和饲料中,作为营养补充剂。 Which kelp is one of the most iodine-rich foods on the planet, seaweed powder can be added directly to a source of iodine in food and feed, as a nutritional supplement.

目前,市场上对海带、裙带菜等食用褐藻的加工形式有干燥、盐溃等,既便于长时间保存,又增加口感。 Currently, the market has to kelp, wakame edible brown seaweed processing in the form of dry, salinization, etc., both for long-term storage, but also increase the taste. 此外,海带常见的简单的加工形式为制成海带粉。 In addition, kelp common form is a simple process made kelp powder. 海带粉的工艺流程为:原料海带一水洗一浸泡一脱腥一晾晒一切碎一干燥一粉碎一过筛一成品海带粉。 Kelp powder process: a seaweed starting material a water soak fishy a shredder drying a sieving a dried pulverized finished a kelp powder. 整个过程只是对海带进行物理的粉碎变化,水洗可以祛除溶于水的无机砷,但是不能祛除铅、镉等重金属,而其中的海藻多糖是以高分子状态存在,只能作为普通的膳食纤维,不仅不能被吸收,而且还影响其他有效成分的利用率。 The whole process just physical changes seaweed was pulverized, washed with water can eliminate water-soluble inorganic arsenic, but can not eliminate the heavy metals lead, cadmium, and wherein the seaweed polysaccharide is a polymer state exists only as a normal dietary fiber, not only can not be absorbed, but also the efficiency of the other active ingredients.

中国发明专利200610154800. 4水溶性海藻粉的制备。 Preparation of water-soluble seaweed powder Chinese patent 200610154800.4. 该法通过酶解、加碱转化制备的海藻粉可在水中溶解。 The enzymatic splitting method, seaweed powder may be prepared by conversion of alkali dissolved in water. 但是在长时间的加工过程中,海带表面的褐藻胶、甘露醇、水溶性的维生素、矿物质等溶解流失,使海藻粉中的活性物质大大损失,而其中的海藻多糖没有降解,仍为高分子态,难以被吸收。 However, in the process for a long time, the surface of the seaweed alginate, mannitol, water-soluble vitamins, minerals and other dissolved loss of the active material in the seaweed powder is lost greatly, and wherein the seaweed polysaccharide is not degraded, it is still high molecular, difficult to absorb.


针对现有技术中海藻提取物中活性成分往往大大流失的缺陷,本发明提供了一种活性海藻提取物的制备方法。 The disadvantages of the prior art for a seaweed extract active ingredients are often much loss, the present invention provides a method of preparing active extracts of seaweed. 本发明制备的活性海藻提取物保留了海藻原有营养成分,而且其中的多糖成分得到了有效降解,通过加入益生菌发酵,使其具有更好的生物活性。 Activity seaweed extract prepared in the present invention retain the original nutrients seaweed, and wherein the polysaccharide component has been effectively degraded by the addition of probiotic fermentation, so as to have better biological activity.

为解决上述技术问题,本发明采用以下技术方案予以实现: To solve the above problems, the present invention employs the following technical solutions to be achieved:

一种活性海藻提取物的制备方法,所述方法包括下述步骤: Method for preparing an active seaweed extract, said method comprising the steps of:

(I)挑选整洁无霉烂的海藻,剔除杂藻及异物; (I) without selection neat rotten seaweed, algae and foreign matter removed heteroaryl;

(2)将上述除杂后的海藻用PH2-4的稀酸溶液进行清洗、绞碎,并在PH2-4的稀酸的溶液中磨碎匀浆; (2) After the impurity seaweed carried out with a dilute acid solution PH2-4 washed, minced, ground and homogenized in a dilute solution of PH2-4;

(3)将匀浆后的海藻,在温度121〜135°C,压力I〜5MPa下熟化灭菌O. 5〜2小时,降解多糖类成分; (3) the alginic after homogenization, sterilization O. aged at a temperature of 121~135 ° C, a pressure I~5MPa 5~2 hours, the degradation of polysaccharide component;

(6)发酵后的浆液中加入褐藻胶低聚糖进行调配,对益生菌进行保护、增殖,调配后的浆液即可作为活性海藻提取液产品,或可经干燥制成活性海藻提取粉产品。 After the slurry (6) was added to fermented alginate oligosaccharide deployment, probiotics protection, proliferation, after the slurry can be formulated as an active seaweed extract product, or may be made active seaweed extract dried powder products.

对技术方案的进一步改进:所述步骤(I)中海藻为褐藻中的海带、羊栖菜、昆布或裙带菜中的一种或几种。 Further improvement of the technical solution: the step (I) in one or more of seaweed alginate in seaweed, hijiki, kelp or seaweed in.

对技术方案的进一步改进:所述步骤(2)中稀酸溶液为硫酸、硝酸或醋酸中的一种或几种。 Further improved technical solution: the step (2) in a dilute acid solution to one or more of sulfuric acid, nitric acid or acetic acid.

对技术方案的进一步改进:所述步骤(2)中清洗方式为浸洗;稀酸溶液质量为海藻质量的3〜10倍;浸洗时间为O. 5〜2小时。 Further improvement of the technical solution: in the step (2) in the cleaning method of dipping; dilute acid solution is 3~10 mass times the mass of seaweed; O. 5~2 hours immersion time.

对技术方案的进一步改进:所述步骤(2)中匀浆时所用稀酸溶液的质量为海藻的8〜12倍。 Further improvement of the technical scheme: said step of dilute acid solution with a mass of seaweed (2) when homogenized 8~12 times.

对技术方案的进一步改进:所述步骤(4)中PH调整所用碱为氨水、氢氧化钾、碳酸钾或氢氧化钙中的一种或几种。 Further improved technical solution: the step (4) is used to adjust the PH base is one or more of ammonia, potassium hydroxide, potassium carbonate or the calcium hydroxide.

对技术方案的进一步改进:所述步骤(5)中益生菌为双歧杆菌和/或乳酸菌。 Further improved technical solution: the step (5) in the probiotic bifidobacteria and / or lactic acid bacteria.

对技术方案的进一步改进:所述步骤(5)中益生菌的接种量为海藻浆液体积的 Further improved technical solution: the step (5) the amount of the probiotic inoculum volume of slurry of seaweed

2 〜5%。 2 ~ 5%.

对技术方案的进一步改进:所述调配用褐藻胶低聚糖的质量与发酵后浆液的质量比为(2〜5) :100。 Further improved technical solution: with the formulation of alginate oligosaccharide mass and mass ratio of the slurry after fermentation (2 ~ 5): 100.

对技术方案的进一步改进:所述褐藻胶低聚糖为100〜700mpa. s的10%褐藻胶低聚糖。 Further improvement of the technical solution: the alginate oligosaccharide 100~700mpa s 10% of the alginate oligosaccharides.

与现有技术相比,本发明的优点和积极效果是: Compared with the prior art, the advantages and positive effects of the present invention are:

I、本发明采用稀酸洗涤海藻,在达到洗涤效果的同时,部分无机盐、甘露醇等水溶性成分和砷、铅、鉻等有害重金属离子得到祛除,其中无机碘部分被祛除,但有机碘完全保留在藻体中;酸性处理后高温高压处理,可彻底杀死顽固的细菌孢子,降解藻体内的多糖类成分,有利于后续益生菌的发酵。 I, the present invention is washed with dilute acid algae, while achieving the washing effect, part of the harmful heavy metal ion salts, mannitol and the like and water-soluble components of arsenic, lead, chromium, etc. to give wipe, wherein the inorganic iodine partially eliminate, However, organic iodine completely retained in the algal biomass; high temperature and pressure treatment after acid treatment, the refractory can completely kill bacterial spores, algae vivo degradation of the polysaccharide component, probiotics facilitate a subsequent fermentation.

2、本发明还在海藻提取物中加入褐藻胶低聚糖,可有效保护益生菌;并且褐藻胶低聚糖本身也是一种具有独特生理功能的活性物质。 2, the present invention also seaweed extract was added algin oligosaccharides, can effectively protect the probiotics; and alginate oligosaccharide is itself a physiological function has a unique active substance.

3、本发明制备的活性海藻粉具有低聚海藻多糖的功能,易于吸收,利用率高。 3, active seaweed powder according to the invention has a function of preparing the oligomeric seaweed polysaccharides, easily absorbed, high utilization rate. 具体实施方式 Detailed ways

下面结合具体实施方式对本发明作进一步详细的说明。 DETAILED DESCRIPTION The following embodiments of the present invention will be further described in detail.

实施例I Example I

本发明所述一种活性海藻提取物的制备方法包括以下步骤: A method of preparing the active seaweed extract of the present invention comprises the steps of:

(I)挑选整洁无霉烂的海带1kg,剔除杂藻及异物; (I) without selection neat rotten seaweed 1kg, algae and foreign matter removed heteroaryl;

(2)称取5Kg自来水,用硫酸调整PH为3左右,将海带浸入翻搅浸洗I小时; (2) Weigh 5Kg water, adjust the PH of about 3 with sulfuric acid, immersed in the seaweed I welling hours immersion;

(3)将清洗后的海带绞碎后,加入PH为3的稀硫酸8kg —起匀浆; (3) After washing the seaweed minced, dilute sulfuric acid was added PH 3 to 8kg – from homogenate;

(4)将匀浆后所得海带浆,于125°C、3 MPa下,保持I小时,熟化灭菌并降解多糖类成分; (4) The resulting homogenate slurry kelp, at 125 ° C, under 3 MPa, kept I hour, sterilized and aged degradation of a polysaccharide component;

(5)将降解后的藻浆液加氨水调整PH至6. 5 ; (6)在调整PH后的海藻浆液中,按体积比3%接种预先培养好的双歧杆菌菌种于37°C条件下,厌氧发酵24小时; (5) The aqueous ammonia was added alginate slurry was adjusted to 6.5 PH degradation; (6) seaweed slurry was adjusted PH, the ratio by volume of 3% pre-culture was inoculated good bifidobacterium at 37 ° C for kinds of conditions, anaerobic fermentation 24 hours;

(7)发酵后的浆液中加入O. 3K g褐藻胶低聚糖进行调配,对益生菌进行保护、增殖; (7) was added to the slurry after fermentation O. 3K g algin oligosaccharides be formulated, probiotics protection, proliferation;

(8)调配后的浆液即可作为活性海藻提取液产品,或可经干燥制成活性海藻提取粉广品。 (8) after the slurry can be formulated as an active seaweed extract product or wide product was dried extract powder made active seaweed.

实施例2 Example 2

本发明所述一种活性海藻提取物的制备方法包括以下步骤: A method of preparing the active seaweed extract of the present invention comprises the steps of:

(I)挑选整洁无霉烂的海带30kg,羊栖菜70kg,剔除杂藻及异物; (I) without selection neat rotten seaweed 30kg, hijiki 70kg, algae and foreign matter removed heteroaryl;

(2)称取600Kg自来水,用硝酸调整PH为3左右,将海带浸入翻搅浸洗I. 5小时; (2) Weigh 600Kg water, adjusted PH to about 3 with nitric acid, seaweed immersed welling immersion I. 5 hours;

(3)将清洗后的海带绞碎后,加入PH为3的稀硝酸800kg —起匀浆; (3) After washing the seaweed minced, PH is added to dilute nitric acid 800kg 3 – from homogenate;

(4)将匀浆所得海带浆,于125°C、3 MPa下,保持I小时,熟化灭菌并降解多糖类成分; (4) The resulting homogenate seaweed slurry at 125 ° C, under 3 MPa, kept I hour, sterilized and aged degradation of a polysaccharide component;

(5)将降解后的藻浆液加氢氧化钾调整PH至6. 5 ; (5) After the slurry is degraded alginate potassium hydroxide to adjust PH to 6.5;

(6)在调整PH后的海藻浆液中,按体积比4%接种预先培养好的乳酸菌菌菌种于37°C条件下,厌氧发酵24小时; (6) seaweed slurry after the PH adjustment, 4% by volume inoculated precultured lactic acid bacteria by good at 37 ° C for conditions of anaerobic fermentation 24 hours;

(7)发酵后的浆液中加入40公斤褐藻胶低聚糖进行调配,对益生菌进行保护、增殖; (7) fermenting the slurry was added to 40 kg of alginate oligosaccharides be formulated, probiotics protection, proliferation;

(8)调配后的浆液即可作为活性海藻提取液产品,或可经干燥制成活性海藻提取粉广品。 (8) after the slurry can be formulated as an active seaweed extract product or wide product was dried extract powder made active seaweed.

实施例3 Example 3

将与实施例2相同质量、数量的海带按上述步骤进行试验,其中仅将洗涤、匀浆时所加稀酸更换为自来水,进行对照试验,则高温高压降解后的海藻浆液,用氨水调整PH至 The number of the same quality for kelp embodiment described above in Example 2 step test in which only the washing, dilute acid added when the homogenate is to replace the water, a control test, the degradation of the high temperature and pressure slurry of seaweed, with ammonia water to adjust the PH

6. 5后,具体对比如表I。 After 6.5, such as specific for Table I.

表I :酸性条件降解效果对照表。 Table I: acidic degradation table.

以上实施例仅用以说明本发明的技术方案,而非对其进行限制;尽管参照前述实施例对本发明进行了详细的说明,对于本领域的普通技术人员来说,依然可以对前述实施例所记载的技术方案进行修改,或者对其中部分技术特征进行等同替换;而这些修改或替换,并不使相应技术方案的本质脱离本发明所要求保护的技术方案的精神和范围。 The above embodiments are intended to illustrate the present invention, but not intended to be limiting;. Although the present invention has been described in detail embodiments, those of ordinary skill in the art, the foregoing can still the technical solutions described in the embodiments may be modified, or some technical features equivalents; as such modifications or replacements do not cause the essence of corresponding technical solutions to depart from the spirit and scope of the invention as claimed technical solution.


Grow More Seaweed Extract offers a all natural organic non-toxic product that leaves no residue on crops. May be applied anytime during the growing season through harvest.

Growers can expect a variety of benefits from using Grow More Seaweed Extract. Research and field trials have demonstrated benefits such as improved root development, more vigorous growth, increased resistance to environmental stress and reduced frost damage.

Our Grow More Seaweed Extract contains naturally balanced chelated trace elements such as boron, molybdenum, copper, zinc, manganese, iron, and cobalt. The natural chelating agents are alginic acid and mannitol.

Seaweed Extract contains low concentration of naturally occuring plant growth factor. As a foliar spray, use 1 teaspoon (5 grams) per gallon of water or use 11 ozs. (310 grams) in 50 to 100 gallons (189-380 liters of water per 4,050 sq. meters) of water per acre. Apply foliar spray as fine-misting spray to wet foliage. A biodegradable sticker/spreader like Grow More spray enhancer can be used to maximize dispersal and adhetence.

Do not apply in the heat of the say or in dty windy conditions. Early morning or late evening applications are best. Best results will be achieved by making more frequent applications every 2 to 3 weeks rather than increasing the concentration of the spray solution.

FRUIT TREES, GRAPES, BERRIES OTHER VINES: A minimum of 6 applications during the season is recommended 1st spray begins at sign of first growth in Spring 2nd spray at pink bud; 3rd spray at fruit set; Subsequent sprays every 2 to 3 weeks. STARWBERRIES: 1st spray when there is sufficient leaves 2nd spray at first bloom; 3rd spray at fruit set (Subsequent sprays every 2 to 3 weeks thru picking).


NURSERY/GREENHOUSE: Develop more compact plant, larger root system, darker green foliage, enhance color or bloom. DIRECT USE DILUTION FOR SOIL DRENCH: Use I quart per 250 gallons of water or I liter Seaweed Extract per 1,000 liters of water for 10 ppm Seaweed.

INJECTOR SYSTEM: Intermittent Feeding (1: 100 Injector Ratio) – Add 44 to 48 fl. ozs. per 100 gals Injector tank. Add with existing fertilizer for 10 ppm (1.24 to 1.36 liters Seaweed per 380 liters of water). Apply every 3 to 4 weeks throught olit active growing period for 10 ppm Seaweed. Constant Feeding (I: 100 Injector Ratio) – Add 9 fl. ozs. per 100 gals. Injector Tank for 2 ppm Seaweed.


BEANS, PEAS: 1st spray at 4 to 6-inch stage; 2nd spray at pre-flower; 3rd spray at bloom.

BROCCOLI, CAULIFLOWER: 1st spray at 4 to 6-inch true leaf stage; CABBAGE 2nd spray at head initation.

CARROTS, ONIONS, LEEKS: 1st spray when foliage is large enough to spray 2nd spray at root enlargement time.

EGGPLANTS, PEPPERS: 1st spray at 4 to 6-inch growth stage; 2nd spray at root enlargement time.

TOMATOES: 1st spray at 6 to 8-inch growth stage; 2nd spray at pre-bloom; 3rd spary at fruit set; 4th spray at 2 to 3 weeks later.

SEED TREATMENT: To help break dormancy, coat seeds briefly ina solution of 1 oz to 2 gals. of water.

TRANSPLANT SOLUTION: Soak roots to help reduce transplant shock briefly in a solution of 1 oz. per 2 gals. of water prior to planting.


ALFALFA, HAY: 1st spray in early Spring & FORAGE CROPS Repeat every 2 weeks after each cutting or have pasturing.

CORN: 1st spray at 4 to 6-inch growth stage; 2nd spray at 10 to 14-inch growth stage. 3rd spray just before tasseling.

SOYBEANS: 1st spray in early Spring; 2nd spray at full bloom. Follow with 2 more sprays at 2 to 3-week intervals.

SUNFLOWERS AND OTHER: 1st spray at seedling stage OIL SEED CROPS 2nd spray at flowering.

SMALL-GRAIN CROPS: 1st spray at 4 to 8-inch growth stage; 2nd spray at lowering or seedhead time Subsequent sprays at 2 to 3-week intervals, if desired.

TURFGRASS: Apply 1 to 2 quarts per acre at 2 to 3 weeks intervals.

How to Use Seaweed to Mulch Your Garden

Benefits of seaweed for gardening

Gathering seaweed for the garden has always been a favorite outing for our family. We usually take a small skiff to a nearby beach and load up with as many sacks as we can safely transport home. It’s fun for children, as they can participate as well as an adult, or they can simply enjoy the beach while we gather the seaweed. As we fill up our sacks, our thoughts drift to the many benefits this will bring our garden.

  • Saves water, keeps soil moist at ground level

    The purpose of any mulch is to keep garden soil from drying out at the surface. And by preventing moisture from evaporating, mulch reduces the need for watering. The practice of mulching is essential in areas where conditions are hot and dry.

  • Eliminates the need to weed
    Mulch covers the soil and blocks new weeds from sprouting. Because the soil beneath the mulch remains moist, any weeds which do manage to sprout through the mulch are easy to pick.
  • Repels slugs and other pests

    Slugs are immediately repelled by two things – salt and sharp-edged materials. Seaweed has a natural salt content which repels slugs, and within a few days of application it dries and becomes quite crispy. Slugs do not like “crispy” surfaces, as the sharp salty edges cut into the soft body tissue. While some mulches may provide hiding spots for slugs, earwigs and other pests, seaweed mulch does not have this disadvantage.

  • Enriches the soil
    Seaweed is a broad spectrum fertilizer that is rich in beneficial trace minerals and hormones that stimulate plant growth. Seaweed is high in carbohydrates which are essential building blocks in growing plants, and low in cellulose so it breaks down readily. Seaweed shares no diseases with land plants.
  • Boosts lethargic plants
    Seaweed fertilizer contains an abundance of fully chelated (ready to use) micro-nutrients which can be readily absorbed by plants without any further chemical decomposition needed.
  • Helps lighten the soil
    Compacted soil can benefit as seaweed mulch breaks down. As the material becomes incorporated into the soil, aeration is improved and the soil becomes more crumbly and moist.
  • Does not contain weed seeds, unlike bark mulch
    Two years ago we used commercial bark mulch to cover our garden pathways for the purpose of blocking weeds. Today, these pathways are sprouting horsetail, an invasive weed which can be difficult to eradicate. Seaweed does not bring any foreign weed seeds into your garden.
  • It’s free!

But what about salt? Is this a problem?
We have been using seaweed as mulch for many years and have not seen any adverse effect, such as a salt overload in the soil. In our region we have plentiful rain. If you are concerned about salt, seaweed can be spread out over the driveway and rinsed with a hose. Of course this is not an issue if you are using freshwater lake weed.

Americans can get it here

Canadians can get it here

Plants have to deal with a lot of environmental stress.

This includes heat, cold, wind, drought and disease.

That’s where liquid seaweed fertilizer comes in.

Seaweed for plants has been used by gardeners and farmers for thousands of years.

People have collected it off the beach and put it right on their gardens as a seaweed fertilizer diy and mulch that quickly broke down, releasing dozens of minerals and vitamins and other beneficial components.

When I lived near the ocean on the west coast, I would drive to a nearby beach to do the same.

But nowadays I use liquid seaweed fertilizers instead, made from one of the most common seaweeds: kelp.

Kelp is a wonderful soil amendment, but when we don’t have it around, a seaweed liquid fertilizer still brings many of the same benefits.

And a big advantage of these liquids over the solids is that we can spray them onto plant leaves for direct leaf uptake.

When you do that, the plants get a nice shot of dozens and dozens of different minerals and vitamins.

But the main benefit of liquid seaweed is the natural plant growth regulators and hormones it contains that help plants grow faster, healthier and stronger.

And one of the main things they do is help plants deal with those environmental stressors.

Benefits Of Liquid Seaweed Fertilizer

These record-breaking watermelon were grown with my liquid seaweed fertiliser and liquid fish.

Probably the most important of seaweed fertilizer benefits is that it’s the best when it comes to boosting plant health and helping plants deal with environmental stressors such as heat, cold, wind, drought and disease.

Like all of my organic fertilizers, it can have a big impact on boosting plant growth, but I often think of it as really excelling at promoting healthier plants.

Using seaweed as fertilizer also increases overall nutrition, including protein content (the protein content of our crops has dropped considerably since WWII).

Seaweed feed has been well studied and has become a mainstay of organic farming and gardening. T. L. Senn did a lot of research on using seaweed as a fertilizer back in the day. He eventually wrote a great little book called ‘Seaweed and Plant Growth.’

His research showed not only the kelp fertilizer benefits for plant health and growth, but also that a quality liquid seaweed can help control insect pests such as spider mites.

Who Needs This The Most?

The reason I recommend this to everyone is that it really is helpful in most gardens.

It doesn’t necessarily give the big boost in plant growth that some products give, but it does boost plant health, which helps discourage pests.

It’s just a nice piece of preventative health care to bring into the mix, and at times can be a quick cure for various ailments a plant may encounter.

That’s why organic farming consultants often recommend it be included in any spray application regardless of what else is being used.

Seaweed Fertilizer Make Your Own

How to make seaweed fertilizer: if you live near a beach with some seaweed on it, you can just take that and use it directly as a seaweed garden mulch, provided it’s legal in your area to remove it.

Be sure to leave some for the beach, though, as it has a big role to play there as food and habitat for many different species.

Or if you want to make a basic liquid seaweed fertilizer, pack the seaweed into an airtight container and fill it with water.

You don’t have to rinse off the salt first.

Let it sit for at least a couple of weeks (or more like a couple of months in cold weather).

It smells quite bad because it’s an anaerobic fermentation, but that’s okay. Adding a bit of EM into the water can cut down on that.

When you’re ready, mix it with 10 parts water and spray it directly onto your plants. It’s not as concentrated as a professionally manufactured kelp fertiliser but will still have many benefits.

If you let it sit long enough, the seaweed will probably decompose and dissolve, but if there’s any left, you can still throw it onto your garden as a mulch.

Finding A Quality Liquid Kelp Fertilizer

Some seaweeds can grow over 2 feet per day.

There are several species of seaweed that are commonly used for fertilizer.

There are debates as to which one is best, but the similarities are far more important than the differences, so when you’re looking for a seaweed garden fertilizer, my view is to not worry too much about the species.

What’s more important is that the kelp plant food is processed without heat and high pressure, so as to keep as many of the beneficial components intact.

Even some of the organic products – like the popular Maxicrop liquid seaweed – are processed in such a way that they don’t retain nearly as many of the natural growth regulators and beneficial microbes. That’s not to say products like that wouldn’t have any benefit, but they’re definitely not the same quality.

The other thing to think about is whether the manufacturer is sustainably harvesting the seaweed, because overharvesting is becoming an issue. That can be more difficult to figure out.

What I do is contact the manufacturer to ask what they’re doing to make sure their process is sustainable. If they have a good answer instead of brushing me off, that’s a good start. Then I go to the internet to see if anyone else has any more info on the company.

I would like more solid info that that, but seaweed harvesting is not an issue under public scrutiny at this point, even by environmental organizations, so I mostly have to go by word of mouth.

The liquid seaweed fertilizer I use is from Neptune’s Harvest, cold processed and organic. I did some digging and found that it’s made by Thorvin, one of the best seaweed manufacturers in the world when it comes to quality and sustainability.

In terms of quality, they dry the seaweed at low temperatures using geothermal energy in order to retain the nutrients and preserve bioavailability.

In terms of sustainability, they harvest in a geographically remote location, in very clean water, away from agricultural run-off and commercial shipping. They also rotate harvests to allow for sufficient regenerative growth.

How To Use Seaweed Fertilizer

Use 1 quart per 1000 square feet annually.

So I use 1/2 cup of liquid seaweed fertilizer per 1000 square feet every month for 8 months.

Mix it with at least 50 times as much water, which is 1/3 cup (5 Tbsp) per gallon of water, or 1.5 gallons of water for each 1/2 cup of fertilizer.

It goes great with any other liquid product, which is why it ends up in my mix every month.

Liquid seaweed is great mixed with liquid fish and molasses/dextrose. It also goes well with EM, compost tea and mycorrhizal fungi.

You can soak/spray your seeds and root balls to improve germination and early root growth, and decrease transplant shock. Do that at the same ratio above. I often soak seeds overnight before planting.

You Can Get It Here

In summary, this liquid seaweed fertilizer:

  • Provides many benefits, but is especially known for improving plant health and helping plants deal with heat, cold, wind, drought and disease.
  • Is manufactured sustainably, without heat and pressure, therefore providing much more benefit than other brands.
  • Is organic (OMRI-Listed) and undoubtedly one of the most popular organic fertilizers available.

As a free bonus when you order today, I’ll also enroll you in my online Biostimulants course.

Just choose your container size and click ‘Add To Cart’ up above!


  • Shipping is $10 (if your order is $99 or less) or free (if your order is $100 or more).
  • I ship in the U.S. only. I ship 7 days a week.
  • All of my products have a 1 year 100% money-back guarantee.
  • If you have a question about a product, leave it in the comment section below I’ll try to respond within a few hours.
  • Dry fertilizers and compost tea brewers ship separately so they will arrive on their own maybe a day or 2 apart from my other products.
  • With every order, I send $1 to Organics 4 Orphans and other similar organizations. O4O is working with the world’s poor to help them grow organic, highly nutritious, highly medicinal food for themselves, and then use the surplus food to generate income for themselves as well as feeding the orphans in their communities. My hope this year is to again send $1500US, which is enough to start projects in 25 new communities!

Free $25 Bonus When You Buy Today

When you buy this liquid seaweed fertilizer, you get enrolled in my online Biostimulants course.

The course includes 10 videos totaling about 75 minutes where I chat about seaweed, fish, sea minerals, molasses/dextrose, rock dust, and how to use them all.

How To Create Your Own Seaweed Fertilizer

Seaweed fertilizer is known for its healthful benefits, like adding up to 60 trace elements to your mulch or compost. Seaweed also contains many growth hormones and disease control properties. Because of these factors, plants treated with this type of fertilizer have access to virtually every nutrient they could ever need. Seaweed also provides food for the beneficial fungi in your soil. Not only is it inexpensive to make seaweed fertilizer, but it is organic and eco-friendly.

Step 1 – Put It Together

The first thing you need to do is to put your seaweed into the bucket and add the warm water. Stir up your mixture well, and seal up the bucket.

Step 2 – Let It Rot

The benefits of seaweed fertilizer don’t come from using fresh seaweed. Rather, they come from using decayed seaweed. Let your mixture rot in the bucket, opening it to stir your mixture every few days. This process should take about a month. Once it is rotted, the water will turn brown and murky, and it will have a rotten plant matter smell to it. You’re already halfway through your process!

Step 3 – Dilute Your Concentrate

The rotted mixture in your bucket is your seaweed fertilizer concentrate. In order to use your fertilizer, you must dilute it with more water. The recommended proportion is 1:16, and so when you add the correct amount of seaweed fertilizer concentrate to water, it is ready to use.

Step 4 – Apply Fertilizer

The best way to apply the ready-to-use fertilizer is to put it in a garden spray bottle. These are tanks with long spray nozzles at the end of a hose. To use your fertilizer, put your diluted concoction into a garden sprayer, and spray it over your flowers and vegetables. Allow the mixture to sink into the soil as many of the nutrients can only be absorbed through the roots of the plants. This is especially important for root vegetables like potatoes, carrots, beets and onions.

Fertilize with a seaweed fertilizer once a month, or more if necessary. Rain can wash nutrients away, and if the soil is dry, then the vitamins are unavailable to the plants because they’re immobile. As always, fertilizer should be used at the beginning of your planting to ensure healthy germination for your seeds.

If you would like, you may add a fish emulsion to your seaweed fertilizer. This can add other trace elements and nutrients to your soil upon application. If odor is a problem, you can also supplement your fertilizer with molasses. The sugars in molasses help to control the rotting smell, as well as promote good microbial growth by feeding the aerobic bacteria with the simple sugars. The combination of all these steps can bring you a stunning flower garden or a healthy, robust vegetable garden every year.

Seaweed for Plants

Long ago, gardeners who lived near the ocean learned that seaweed was good for their plants. Exactly how it works is difficult to pin down, but scientists have found in seaweeds a veritable soup of plant-growth stimulants, vitamins, chelating agents, trace minerals, enzymes, and amino acids, all of which influence the growth of plants in different ways.

Robert Parnes in his classic Organic & Inorganic Fertilizers (Woods End Agricultural Institute, 1986; $40) says, “Perhaps the most important merit of seaweed is its content of assimilable organic materials, in particular the growth hormones.”

Seaweeds contain small amounts of nitrogen, phosphorus, and potassium. On a dry-weight basis, seaweeds contain up to 1.2 percent nitrogen, 0.2 to 1.3 percent phosphorus, and 2.8 to 10 percent potassium.

Several university studies have shown that seaweed can produce dramatic results in plants: geraniums produced more flowers per plant; grapes were sweeter; gladiolus corms grew larger; and cucumber yields increased 40 percent and the fruits suffered less often from softening and rotting. Improved yields after seaweed treatments were measured in potatoes, sweet corn, peppers, tomatoes, apples, strawberries, okra, and oranges. Better frost tolerance, increased seed germination, and greater capacity to absorb trace elements were other documented benefits for plants.

Seaweed for Gardeners

When gardeners talk about using seaweed on their plants, they are usually referring to a brown algae, specifically the one known as knotweed or rockweed (Ascophyllum nodosum). It’s common off the coast of Norway but also grows along the American coast from northern Maine to Canada and throughout northern seas. The seaweed industry had an early start in Norway where seaweed supply was abundant, hence the “Norway” on the labels of many seaweed products.

The seaweed product that’s been around longest (40 years) is Maxicrop. It is normally sold as a concentrated dry powder that you mix with water and apply to plants as a spray. But it is also available as a liquid concentrate, as are most other seaweeds.

Most liquid seaweed fertilizers are extractions manufactured by hydrolysis, and most of the basic research done with seaweeds (by T. L. Senn, formerly of Clemson University) used this form. You might read about liquid seaweed products that are “cold-pressed” or “enzymatically digested”, but little research exists regarding these materials. Seaweed is also available as a dry meal intended for adding to soil. Liquid concentrates cost more than the powders, but they are much easier to mix with water.

Another seaweed fertilizer is derived from California bull kelp (Nereocystis luetkeana). It is offered only by Peaceful Valley Farm Supply, whose catalog claims this fertilizer is more potent than ascophyllum-based products, but I haven’t seen any research to back up such claims.

Using Seaweed

I recommend using seaweed extracts on plants where irregularly yellowed foliage suggests a micronutrient deficiency. Diagnosing such hunger signs is very tricky for most home gardeners. The surest way to know–a leaf-tissue analysis–is expensive, which is why applying the broad spectrum of micronutrients found in seaweed extracts to your plants may be an efficient remedy.

A deficiency of micronutrients in the soil rarely causes a deficiency in the plants. Micronutrient deficiencies in the plants are commonly caused by soil that has poor structure, is poorly drained, is cold, or has a pH that is too high or too low. In these situations, the tonic of a seaweed spray can help the most.

I’ve tried seaweed sprays on yellowing citrus plants with only limited success. Although seaweed sprays have a natural iron chelate (a chemical that aids iron absorption), the response of citrus to synthetic chelates is often noticeably quicker than to seaweed.

Apply seaweed meal to soil, or apply extracts as a liquid soil drench or onto leaves. Nutrients applied directly to leaves are absorbed and then pass into the plant’s circulatory system. Once there, the nutrients are distributed throughout the plants’ tissues.

Most liquid extracts require dilution in the range of 1 to 2-1/2 ounces per gallon of water. To mix powders (1/4 teaspoon per gallon) easily, treat them like a gravy. First mix a small amount of water with the powder to make a thick, smooth paste and dissolve lumps. Then, add the paste to the full volume of water. Apply seaweed meals at the rate of 1 to 3 pounds per 100 square feet.

Follow the dilution rates and spraying intervals recommended on the container. Don’t assume that using more than label-directed amounts of a benign material like seaweed can’t hurt. Studies have shown that at greater than recommended concentrations, seaweed sprays can actually retard the growth of plants.

Foliar seaweed sprays are best applied to plants with a pressurized tank or backpack-type sprayer. These devices are much better than a hose-end or siphon-type sprayer because they can spray a very fine mist, which allows more solution to stay on the leaves rather than drip to the ground. There is also evidence that a fine mist allows more rapid or efficient absorption of the seaweed in the water.

Be sure to thoroughly cover the undersides of leaves as well as the tops. Then carefully clean the sprayer, so the nozzle isn’t clogged next time.

When to spray. Leaves take a “siesta” in the midday heat and won’t readily absorb the spray, so the best time to spray is early morning or evening. If your plants display any signs of disease, spray only in the morning, so the leaves will dry quickly and reduce the infection’s spread.

Foliar sprays are absorbed relatively quickly, in 1 to 24 hours. Should it rain within a day, respray. Likewise, don’t irrigate plants from above until a day after spraying.

Using a spreader-sticker (a soaplike material that makes sprays spread over and adhere to plants) will improve the efficiency of the seaweed spray. Most spreader-stickers are made from petroleum products, though some gardeners use soy oil, safflower oil, or liquid soap (1/4 teaspoon per gallon) as a natural spreader-sticker.

Composted seaweed. Your plants can also benefit from seaweed’s many nutrients if you collect the material yourself and add it to your compost. Gardeners who live close enough to an ocean may find such a venture practical. However, before collecting seaweed yourself, check with local coastal authorities to be sure it’s legal, and rinse away salt with fresh water.

Are seaweed sprays beneficial? I’ll never forget my experience 15 years ago. I restored a wan, yellow-leaved persimmon tree to green vigor. I did it with a foliar application of seaweed, and, afterward, became a believer in the miracle powers of these ocean plants. Since then, however, results have been mixed. Though seaweed may not always produce the desired results, the cost of an application is relatively low. Though no soil or plant additive will ever replace good gardening practices, only seaweed provides so many key plant micronutrients and growth enhancers in a quickly available form.

Robert Kourik is a horticultural consultant and writer who lives in Occidental, California.

What’s your favorite thing about going to the beach? Relaxing with a good book while soaking in vitamin D? People watching? Collecting shells and sea glass? Now you can add collecting an all-natural garden soil amendment to that list. On the beach Mother Nature offers seaweed, which is one of the best tools for a healthy garden. Read on to learn about the benefits of seaweed for your garden.

How to collect seaweed

Collecting seaweed is as easy as walking on the beach. Couldn’t. Be. Easier.

The only supply necessary to collecting seaweed is a bag. I often use a plastic bag because that’s what I have on hand, but others use burlap bags or onion bags which are great because water can drain out.

Some folks claim that it’s best to collect seaweed that is in the mid beach area–not too close to the water or too far up the beach so that it’s dried out. I’m not so picky and I’ll take whatever I can get.

Once I grab a handful of seaweed I like to give it a shake to allow any sea critters that may be hiding to fall out.

6 Benefits of seaweed to your garden

1. Fertilizer. Seaweed has 60 trace minerals and ready-to-use nutrients including nitrogen, potassium, phosphate, and magnesium. It also contains hormones to encourage plant growth.

Unlike other garden amendments, such as manure, seaweed does not need to decompose before being a benefit to your garden.

2. Mulch. Like all mulches, seaweed helps to keep soil moist thus reducing your need to water the garden. An application of seaweed will reduce how often you need to weed. It contains no seeds that could possibly turn into weeds as bark mulch sometimes does.

Recently I’ve become aware that bark mulch can be a fire danger because it is dry and acts like kindling. Seaweed presents no such danger.

3. Pest control. Slugs especially hate seaweed because of its sharp edges and salt. Birds and other garden pests dislike it for the same reasons.

4. Improved aeration. Seaweed helps aerate the soil just like peat moss does, but it has the added benefit of delivering nutrients and minerals.

5. Prevents fungus and disease. Seaweed helps you to grow strong, healthy plants, and healthy plants resist fungus and disease.

6. Doesn’t blow away. Unlike other compost and mulches, seaweed (especially when it is still wet) won’t blow away in a stiff wind.


Some gardeners worry about the salt in seaweed negatively impacting their garden. I can report that after years of using seaweed in my garden I have no evidence of that negative impact.

Take a moment to check your local beach’s codes before collecting seaweed. You shouldn’t run into a problem with removing seaweed from the beach because you’re not a commercial operation, but it’s best to check first.

How to apply seaweed to your garden

The only thing easier than collecting seaweed is applying it to your garden. Simply place it around plants just as you would compost and/or mulch. Use as much as you can; don’t be skimpy. Your garden beds will appreciate a generous 4-6 inch application.

Related on Organic Authority
7 Reasons Your Garden Will Love Cocoa Mulch
How to Water Plants While on Vacation (Because Dead Plants Kill Vacay Mojo)
How to Improve Your Garden Soil Naturally for the Happiest Garden on the Block

photo of seaweed on beach via

Seaweed Fertiliser

Seaweed is a wonderful fertiliser, a great soil builder and an excellent compost activator. All in all, seaweed is terrific stuff for the garden. There’s a long tradition of seaweed being used as a fertiliser to improve crop production. For example Celtic and Scandinavian farmers have put it onto their fields for centuries.

Kelp is one of many different types of seaweed. One type is powdered kelp. It is convenient for adding to the garden. And what is it about seaweed that makes it such a good fertiliser? Seaweed contains complex carbohydrates and these really get the soil humming with life. This has two really important functions for the garden. Firstly, it stimulates the microbial fungi in the soil and these assist plants in their uptake of nutrients. They also assist in defending plants from soil borne diseases. So adding seaweed fertiliser helps crop protection, and plant nutrition

Of all the fertilisers, seaweed has the broadest and most balanced range of nutrients, to promote early flowering and cropping and increases the sugar content of fruit. All in all, it’s very good stuff.

An extract from seaweed is Algin. It’s sold in the shops as agar agar. Add it to water and make a liquid paste. Pour it onto the soil and it acts like a natural wetting agent. Excellent for sandy soils.

Land plants have cellulose, which thickens their cell walls and allows them to resist gravity, and they can grow upright. Seaweed is supported by water and has no need for cellulose. In a compost heap, that means seaweed breaks down really quickly. It activates the compost heap. But powdered kelp works just as well.

Seaweed also comes in a liquid form, so spray it on plants and they take in the food directly through leaves. Just ensure it’s diluted as recommended, because it’s really strong stuff and can burn seedlings and roots.

Another benefit of using seaweed fertiliser over time is it acidifies and adds iron to the soil, which is great news if you are growing acid and iron hungry plants like gardenias, camellias, azaleas and rhododendrons. It’s great on native plants as well. If you use seaweed fertiliser on native proteaceae, like banksias and grevilleas, just make sure that it hasn’t been fortified with phosphorous, because that can do some harm.

Seaweed contains natural plant hormones, so it’s really useful in preventing transplant shock whenever you move a plant around the garden. It’s also useful for improving the germination of seeds. For example peanuts, which have a large seed, should be soaked for 24 hours in seaweed fertiliser for a good germination rate. Seaweed also helps to improve the thickness of plant cell walls. This makes them much more resistant to pest and disease attack and also improves frost resistance.

Seaweed is easy to use. Apart from the powdered form and the liquid concentrate buy it in an odourless granular form, ideal for house plants. It’s even available in a form that will clip onto the hose and will feed the entire garden. You may be wondering whether it’s possible to make your own seaweed fertiliser. The answer is that you can, but it’s important to first check with your local authority, because collecting seaweed in many parts of the country is illegal and removing it can damage sensitive ecosystems. But using the normal commercially available products can produce pretty good results.

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